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Oceanic Area Control

The Reykjavik CTA is unique in that much of it is also designated as oceanic airspace. This page outlines the specific rules and procedures relevant to oceanic airspace.

As of 20th March 2024, aircraft no longer require oceanic clearance to enter the Reykjavik OCA. This page has been updated with the most current procedures for aircraft entering oceanic airspace.

Oceanic Airspace

Within the Reykjavik CTA, all controlled airspace outside of the Icelandic Domestic Area is considered oceanic airspace. This airspace is designated the Reykjavik Oceanic Area (OCA).

Because the Reykjavik ACC (Area Control Centre) is responsible for the Reykjavik OCA, it is also referred to as the Reykjavik OAC (Oceanic Area Control Centre.) The terms "Reykjavik ACC" and "Reykjavik OAC" are generally interchangeable for VATSIM purposes.

The Reykjavik OCA is one of six oceanic areas that make up the North Atlantic (NAT) oceanic airspace, together with Gander, Shanwick, New York, Santa Maria, and Bodo OFIR (Oceanic FIR).

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VFR is prohibited in oceanic airspace (which is all Class A.) VFR aircraft must either fly below controlled airspace, or request IFR clearance to transit oceanic airspace.

NAT Tracks

The North Atlantic oceanic airspace uses a system of tracks called the North Atlantic Organized Track System (NAT OTS,) to regulate traffic crossing the ocean. While usually remaining in Shanwick & Gander OCAs, the tracks do occasionally enter the Reykjavik OCA.

For an introduction to the NAT OTS, read this guide published by Gander Oceanic on VATSIM. (Ignore the sections on the Tango routes & Concorde tracks, as they are not relevant to BIRD OCA.)

Entering Oceanic Airspace

The NAT oceanic areas is in the process of removing oceanic clearances. BIRD OCA removed oceanic clearances in March 2024. This does not mean, however, that entering BIRD OCA is exactly the same as entering a domestic sector – there are still some additional requirements.

Introduction to RCL Messages

Aircraft entering the BIRD OCA from domestic airspace must submit an "RCL message" – a message that contains the same information they would have originally sent to request oceanic clearance.

  • The acronym "RCL" comes from "Request for Clearance," even though the message is no longer actually used to request a clearance! (Yes, it is confusing...)

An RCL message includes:

  • Oceanic Entry Point (OEP) – i.e., first waypoint in oceanic airspace
  • ETA for the OEP
  • Mach speed
  • Requested Flight Level – i.e., intended flight level at oceanic entry
  • The maximum Flight Level which the aircraft can attain at the OEP

However, instead of receiving a clearance in response to the RCL, aircraft will now (usually) only get a confirmation that their RCL message was received.

  • If oceanic ATC approves of all of the information in the RCL, the aircraft will receive no further messages other than this confirmation.
  • If oceanic ATC needs to change/amend any information in the RCL (e.g., level, speed, routing, etc.), the aircraft will recieve further instructions/re-clearance from ATC as appropriate.

Processing RCL Messages via Nattrak (Primary Method)

On VATSIM, the primary method of receiving & processing RCL messages is via Nattrak (nattrak.vatsim.net), a web platform that simulates the CPDLC systems that are used in real life for submitting & processing RCL messages.

It is not possible to receive/process RCL messages via Hoppies CPDLC.

To be considered valid by Nattrak, RCL messages must be submitted at least 15 minutes prior to oceanic entry. Nattrak will automatically acknowledge all valid RCL messages with the following confirmation message: RCL RECEIVED BY REYKJAVIK CONTINUE TO MONITOR NATTRAK

Aircraft in receipt of this "RCL RECEIVED" message may enter oceanic airspace unless otherwise instructed by ATC.

Regardless of the "RCL RECEIVED" auto-response, controllers shall review all RCL messages received, to ensure that there are no conflicts between aircraft at oceanic entry.

If necessary (e.g., to avoid conflicts, adhere to routing restrictions/standard routings, or other appropriate reasons), controllers may use Nattrak to issue an amended clearance for any element of the RCL. This includes changing an aircraft's:

  • Speed (higher/lower Mach number)
  • Crossing time over the OEP (cross OEP at 1234z / at or before 1234z / at or after 1234z)
  • Level (higher/lower FL)
  • Routing (different random route, NAT track, etc.)

Amended clearances only apply after the aircraft has entered oceanic airspace. E.g., if BIRD re-clears an aircraft to Mach .84, it does not have to change speed right away, but rather only has to enter BIRD at Mach .84.

If one provides a crossing time restriction, it is the pilot's responsibility to adjust their speed so that they enter oceanic airspace at, at or before, or at or after the given time.

If no amendments are required, controllers shall select the Move to Processed List button on Nattrak, which will remove the RCL message from the "Pending" list. (Pressing this button does not send any message to the aircraft.)

Voice Procedures (Fallback Method)

As much as possible, all RCL messages should be processed via Nattrak. However, if an aircraft is unable to submit clearance via Nattrak for any reason (e.g., less than 15 mins before oceanic entry, technical difficulties, etc.), controllers may use voice as a backup.

There is no officially defined phraeseology on how to handle RCL messages via voice. Generally, controllers should use common sense/plain English, and ask aircraft for any information that is necessary to ensure separation. (Usually just the Mach number and flight level is enough.)

🎧 ICE123, report your oceanic Mach number and flight level.

🧑‍✈️ ICE123, Mach .79, FL340.

🎧 ICE123, roger.

Amended clearances may be issued via voice with the phrase "amended speed/level/route clearance," e.g.,

🎧 ICE456, report your oceanic Mach number and flight level.

🧑‍✈️ ICE456, Mach .80, FL340.

🎧 ICE456, amended speed and level clearance, maintain Mach .82, climb FL360.

🧑‍✈️ Maintain Mach .82, climb FL360, ICE456.

Entering/Exiting Other NAT OCAs

Aircraft entering BIRD OCA from other NAT OCAs (e.g., Gander, Shanwick, etc.) do not have to submit an RCL message to BIRD. Permission to enter one NAT OCA serves as permission to enter all of them.

Similarly, aircraft leaving BIRD OCA to another OCA do not have to submit a new RCL message to that OCA. The fact that BIRD OCA has processed their RCL gives the aircraft permission to enter all oceanic airspace in the North Atlantic.

Within Oceanic Airspace

Cost Index (ECON) Operations

In oceanic airspace, aircraft may fly in Cost Index (ECON) mode for optimal fuel efficiency – i.e., they may deviate by up to ±0.02 Mach from the Mach number originally reported to ATC without prior permission. If they deviate by >0.02 Mach from the originally reported Mach number, they must notify ATC.

Controllers may still instruct aircraft to fly a fixed Mach number if required for separation.

A similar procedure was previously known as "Operation Without Assigned Fixed Speed" (OWAFS.) The difference is that now (as of 20th March 2024), pilots are expected to fly ECON mode by default, not just when ATC instructs "resume normal speed."

Strategic Lateral Offset Procedures (SLOP)

Traffic in BIRD OCA above FL285 may use SLOP (Strategic Lateral Offset Procedures). This is a random offset right of the aircraft's track, intended to "artificially" induce a navigation error that reduces the likelihood two aircraft will occupy the same airspace at once.

At pilot's discretion, aircraft with the capability to offset (using their FMS) may offset right of track (left offsets are prohibited) up to a maximum of 2 NM (the exact offset the pilot chooses should be random.) ATC does not need to approve SLOP, or be informed when SLOP is in use. 

Aircraft shall not apply SLOP below FL285 in the Reykjavik OCA, and shall end the use of SLOP before entering domestic airspace.

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